MUSCLES ENGAGED Triceps Triceps are an often forgotten muscle group. Triceps are located on the opposite side of the biceps at the back of the upper arm. Well strengthened and defined triceps make the arm look bigger and sleeker (reducing the "flabby arm" look). Quadriceps The quadriceps (quads) are a group of four muscles on the front of the thigh. They allow your knee to straighten and provide stability when standing. Your quads are the most important muscle group for maintaining the ability to stand and to walk independently. Equipment Used Cable Machine The cable machine is a piece of equipment used in weight training or functional training. A wide variety of exercises can be performed using the apparatus. Exercise Instructions Step 1 Start in a bent over position with a flat back and your arm tucked in to the side of your body. Step 2 Keep your arm in line with your hip and fully extend, contracting the tricep at the end of the motion. Step 3 Return your arm back to the starting position and repeat.